Since 1973 (see DE 2,317,040 C3) and since 1995 (see DE 295 12 567 U1), clamp terminals of this type have been known, which use a rigid, solid support plate comprised of an electrically well-conducting material (e.g, made of a Cu material), which provides a large surface over all terminal sites of a multiple clamp terminal. On this support plate, which provides the electrically conducting connection between the individual clamping sites as well as represents the bearing element for all single clamp terminals joined together into a multiple clamp terminal, a leaf spring tab of spring steel sheet metal is fastened for each single clamp terminal and, in fact, for the most part, in such a way that all leaf spring tabs have a common head piece of spring steel sheet, which is fastened to the support plate by riveting or by clamping, since other, more cost-favorable types of connection between a piece of spring steel sheet and a support plate made of a different material have not been possible.
Due to this relatively expensive type of connection and also because of the higher material consumption for the previously used support plates of large surface that are made of relatively expensive materials, the clamp terminals of this type have come under cost pressure and new developments have been proposed by different manufacturers of clamp terminals, in which the current conducting capacity of the support plate of the prior art is replaced by a conductive core rod, whose material cross section can be better adapted to the required current conduction cross section, and in which the support function of the support plate of the prior art as well as the clamping functions of the individual leaf spring tabs are allocated to a common piece of spring steel sheet, from which the individual leaf spring tabs are punched out. In this connection, see DE Patent 196 54 523 C2 of the Applicant and the Utility Model Specification DE 203 03 537 U1 of the Electro-Terminal company.
These last-named clamp terminals can in fact be produced less expensively than the type of clamp terminals named initially, but have the disadvantage for diverse fields of application that they are constructed too large, in particular, when multiple clamp terminals are required, which have a plurality of single clamp terminals disposed in a row next to one another, as this is shown, e.g., in DE 203 03 537 U1 in FIG. 1.